Search Results

Search found 9253 results on 371 pages for 'console kit'.

Page 74/371 | < Previous Page | 70 71 72 73 74 75 76 77 78 79 80 81  | Next Page >

• Programação paralela no .NET Framework 4 – Parte II

  - by anobre

  Olá pessoal, tudo bem? Este post é uma continuação da série iniciada neste outro post, sobre programação paralela. Meu objetivo hoje é apresentar o PLINQ, algo que poderá ser utilizado imediatamente nos projetos de vocês. Parallel LINQ (PLINQ) PLINQ nada mais é que uma implementação de programação paralela ao nosso famoso LINQ, através de métodos de extensão. O LINQ foi lançado com a versão 3.0 na plataforma .NET, apresentando uma maneira muito mais fácil e segura de manipular coleções IEnumerable ou IEnumerable<T>. O que veremos hoje é a “alteração” do LINQ to Objects, que é direcionado a coleções de objetos em memória. A principal diferença entre o LINQ to Objects “normal” e o paralelo é que na segunda opção o processamento é realizado tentando utilizar todos os recursos disponíveis para tal, obtendo uma melhora significante de performance. CUIDADO: Nem todas as operações ficam mais rápidas utilizando recursos de paralelismo. Não deixe de ler a seção “Performance” abaixo. ParallelEnumerable Tudo que a gente precisa para este post está organizado na classe ParallelEnumerable. Esta classe contém os métodos que iremos utilizar neste post, e muito mais: AsParallel AsSequential AsOrdered AsUnordered WithCancellation WithDegreeOfParallelism WithMergeOptions WithExecutionMode ForAll … O exemplo mais básico de como executar um código PLINQ é utilizando o métodos AsParallel, como o exemplo: var source = Enumerable.Range(1, 10000); var evenNums = from num in source.AsParallel() where Compute(num) > 0 select num; Algo tão interessante quanto esta facilidade é que o PLINQ não executa sempre de forma paralela. Dependendo da situação e da análise de alguns itens no cenário de execução, talvez seja mais adequado executar o código de forma sequencial – e nativamente o próprio PLINQ faz esta escolha.  É possível forçar a execução para sempre utilizar o paralelismo, caso seja necessário. Utilize o método WithExecutionMode no seu código PLINQ. Um teste muito simples onde podemos visualizar a diferença é demonstrado abaixo: static void Main(string[] args) { IEnumerable<int> numbers = Enumerable.Range(1, 1000); IEnumerable<int> results = from n in numbers.AsParallel() where IsDivisibleByFive(n) select n; Stopwatch sw = Stopwatch.StartNew(); IList<int> resultsList = results.ToList(); Console.WriteLine("{0} itens", resultsList.Count()); sw.Stop(); Console.WriteLine("Tempo de execução: {0} ms", sw.ElapsedMilliseconds); Console.WriteLine("Fim..."); Console.ReadKey(true); } static bool IsDivisibleByFive(int i) { Thread.SpinWait(2000000); return i % 5 == 0; }   Basta remover o AsParallel da instrução LINQ que você terá uma noção prática da diferença de performance. 1. Instrução utilizando AsParallel   2. Instrução sem utilizar paralelismo Performance Apesar de todos os benefícios, não podemos utilizar PLINQ sem conhecer todos os seus detalhes. Lembre-se de fazer as perguntas básicas: Eu tenho trabalho suficiente que justifique utilizar paralelismo? Mesmo com o overhead do PLINQ, vamos ter algum benefício? Por este motivo, visite este link e conheça todos os aspectos, antes de utilizar os recursos disponíveis. Conclusão Utilizar recursos de paralelismo é ótimo, aumenta a performance, utiliza o investimento realizado em hardware – tudo isso sem custo de produtividade. Porém, não podemos usufruir de qualquer tipo de tecnologia sem conhece-la a fundo antes. Portanto, faça bom uso, mas não esqueça de manter o conhecimento a frente da empolgação. Abraços.

  Read the article

• Throttling in OSB

  - by Knut Vatsendvik

  Technorati Tags: soa,integration,osb,throttling,overload protection A common problem with integration is the risk of overloading a particular web service. When the capacity of a web service is reached and it continues to accept connections, it will most likely start to deteriorate. Fortunately there are 2 techniques, with Oracle Service Bus, that you can apply for protecting this from happening. You can either limit the concurrent number of requests for a Business Service (outbound requests) or you can limit the number of threads processing the requests for a Proxy Service (inbound requests). Limiting the Concurrent Number of Requests Limiting the concurrent requests for a Business Service cannot be set at design time so you have to use the built-in Oracle Service Bus Administration Console to do it (/sbconsole). Follow these steps to enable it: In Change Center, click Create to start a new Session Select Project Explorer, and navigate to the Business Service you want to limit Select the Operational Settings tab of the View a Business Service page In this tab, under Throttling, select the Enable check box. By enabling throttling you Specify a value for Maximum Concurrency Specify a positive integer value for Throttling Queue to backlog messages that has exceeded the message concurrency limit Specify the maximum time in milliseconds for Message Expiration a message can spend in Throttling Queue Click Update Click Active in Change Center to active the new settings If you re-publish the service, it will not overwrite the settings. Only if the resource is renamed or moved, it will. Please note that a throttling queue is an in-memory queue. Messages that are placed in this queue are not recoverable when a server fails or when you restart a server. Limiting the Number of Threads A better approach, in my opinion, is to limit the number of threads that can work with request. Follow these steps to do it: Open the WebLogic Server Console (/console) In Change Center, click Create to start a new Session In the left pane expand Environment and select Work Managers In the Global Work Managers page, click New    Click the Work Manager radio button, then click Next Enter a Name for the new Work Manager, and click Next In the Available Targets list, select server instances or clusters on which you will deploy applications that reference the Work Manager Click Finish. The new Work Manager now appears in the Global Work Managers page. Select the new Work Manager Right next to the Maximum Threads Constraint drop-down box, click New   Click the Maximum Threads Constraint radio button, then click Next Enter a Name and a thread Count to be the maximum size to allocate for requests. Click Next  In the Available Targets list, select server instances or clusters on which you will deploy applications that reference the Work Manager Click Finish Click Save Click Active in Change Center to active your changes.  A restart may be necessary.   Puh! Almost there. Start a new session. Go to the Service Bus Console (/sbconsole) and find your consuming Proxy Service. Click the Edit button of the Transport Configuration tab. Click Next Set the Dispatch Policy to the new Work Manager Click Last Click Save Click Active in Change Center to active your changes. 

  Read the article

• Beware when using .NET's named pipes in a windows forms application

  - by FransBouma

  Yesterday a user of our .net ORM Profiler tool reported that he couldn't get the snapshot recording from code feature working in a windows forms application. Snapshot recording in code means you start recording profile data from within the profiled application, and after you're done you save the snapshot as a file which you can open in the profiler UI. When using a console application it worked, but when a windows forms application was used, the snapshot was always empty: nothing was recorded. Obviously, I wondered why that was, and debugged a little. Here's an example piece of code to record the snapshot. This piece of code works OK in a console application, but results in an empty snapshot in a windows forms application: var snapshot = new Snapshot(); snapshot.Record(); using(var ctx = new ORMProfilerTestDataContext()) { var customers = ctx.Customers.Where(c => c.Country == "USA").ToList(); } InterceptorCore.Flush(); snapshot.Stop(); string error=string.Empty; if(!snapshot.IsEmpty) { snapshot.SaveToFile(@"c:\temp\generatortest\test2\blaat.opsnapshot", out error); } if(!string.IsNullOrEmpty(error)) { Console.WriteLine("Save error: {0}", error); } (the Console.WriteLine doesn't do anything in a windows forms application, but you get the idea). ORM Profiler uses named pipes: the interceptor (referenced and initialized in your application, the application to profile) sends data over the named pipe to a listener, which when receiving a piece of data begins reading it, asynchronically, and when properly read, it will signal observers that new data has arrived so they can store it in a repository. In this case, the snapshot will be the observer and will store the data in its own repository. The reason the above code doesn't work in windows forms is because windows forms is a wrapper around Win32 and its WM_* message based system. Named pipes in .NET are wrappers around Windows named pipes which also work with WM_* messages. Even though we use BeginRead() on the named pipe (which spawns a thread to read the data from the named pipe), nothing is received by the named pipe in the windows forms application, because it doesn't handle the WM_* messages in its message queue till after the method is over, as the message pump of a windows forms application is handled by the only thread of the windows forms application, so it will handle WM_* messages when the application idles. The fix is easy though: add Application.DoEvents(); right before snapshot.Stop(). Application.DoEvents() forces the windows forms application to process all WM_* messages in its message queue at that moment: all messages for the named pipe are then handled, the .NET code of the named pipe wrapper will react on that and the whole process will complete as if nothing happened. It's not that simple to just say 'why didn't you use a worker thread to create the snapshot here?', because a thread doesn't get its own message pump: the messages would still be posted to the window's message pump. A hidden form would create its own message pump, so the additional thread should also create a window to get the WM_* messages of the named pipe posted to a different message pump than the one of the main window. This WM_* messages pain is not something you want to be confronted with when using .NET and its libraries. Unfortunately, the way they're implemented, a lot of APIs are leaky abstractions, they bleed the characteristics of the OS objects they hide away through to the .NET code. Be aware of that fact when using them :)

  Read the article

• MEB Support to NetBackup MMS

  - by Hema Sridharan

  In MySQL Enterprise Backup 3.6, new option was introduced to support backup to tapes via SBT interface. SBT stands for System Backup to Tape, an Oracle API that helps to perform backup and restore jobs via media management software such as Oracle's Secure Backup (OSB). There are other storage managers like IBM's Tivoli Storage Manager (TSM) and Symantec's Netbackup (NB) which are also supported by MEB but we don't guarantee that it will function as expected for every release. MEB supports SBT API version 2.0 In this blog, I am primarily going to focus the interface of MEB and Symantec's NB. If we are using tapes for backup, ensure that tape library and tape drives are compatible. Test Setup 1. Install NB 7.5 master and media servers in Linux OS. ( NB 7.1 can also be used but for testing purpose I used NB 7.5)2. Install MEB 3.8 also in Linux OS.3. Install NB admin console in your windows desktop and configure the NB master server from there. Note: Ensure that you have root user permission to install NetBackup. Configuration Steps for MEB and NB Once MEB and NB are installed, Ensure that NB is linked to MEB by specifying the library /usr/openv/netbackup/bin/libobk.so64 in the mysqlbackup command line using --sbt-lib-path. Configure the NB master server from windows console. That is configure the storage units by specifying the Storage unit name, Disk type, Media Server name etc.  Create NetBackup policies that are user selectable. But please make sure that policy type is "Oracle".  Define the clients where MEB will be executed. Some times this will be different host where MEB is run or some times in same Media server where NB and tapes are attached. Now once the installation and configuration steps are performed for MEB and NB, the next part is the actual execution.MEB should be run as single file backup using --backup-image option with prefix sbt:(it is a tag which tells MEB that it should stream the backup image through the SBT interface) which is sent to NB client via SBT interface . The resulting backup image is stored where NB stores the images that it backs up. The following diagram shows how MEB interacts with MMS through SBT interface. Backup The following parameters should also be ready for the execution,    --sbt-lib-path : Path to SBT library specific to NetBackup MMS. SBT lib for NetBackup  is in /usr/openv/netbackup/bin/libobk.so64    --sbt-environment: Environment variables must be defined specific to NetBackup. In our example below, we use     NB_ORA_SERV=myserver.com,    NB_ORA_CLIENT=myserver.com,    NB_ORA_POLICY=NBU-MEB    ORACLE_HOME = /export/home2/tmp/hema/mysql-server/ ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ./mysqlbackup --port=13000 --protocol=tcp --user=root --backup-image=sbt:bkpsbtNB --sbt-lib-path=/usr/openv/netbackup/bin/libobk.so64 --sbt-environment="NB_ORA_SERV=myserver.com, NB_ORA_CLIENT=myserver.com, NB_ORA_POLICY=NBU-MEB, ORACLE_HOME=/export/home2/tmp/hema/mysql-server/” --backup-dir=/export/home2/tmp/hema/MEB_bkdir/ backup-to-image ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Once backup is completed successfully, this should appear in Activity Monitor in NetBackup Console.For restore,  image contents has to be extracted using image-to-backup-dir command and then apply-log and copy-back steps are applied. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ./mysqlbackup --sbt-lib-path=/usr/openv/netbackup/bin/libobk.so64  --backup-dir=/export/home2/tmp/hema/NBMEB/ --backup-image=sbt:bkpsbtNB image-to-backup-dir-----------------------------------------------------------------------------------------------------------------------------------Now apply logs as usual, shutdown the server and perform restore, restart the server and check the data contents. ./mysqlbackup   ---backup-dir=/export/home2/tmp/hema/NBMEB/  apply-log ./mysqlbackup --datadir=/export/home2/tmp/hema/mysql-server/mysql-5.5-meb-repo/mysql-test/var/mysqld.1/data/  --backup-dir=/export/home2/tmp/hema/MEB_bkpdir/ innodb_log_files_in_group=2 --innodb_log_file_size=5M --user=root --port=13000 --protocol=tcp copy-back The NB console should show 'Restore" job as done. If you don't see that there is something wrong with MEB or NetBackup.You can also refer to more detailed steps of MEB and NB integration in whitepaper here

  Read the article

• C# 4 Named Parameters for Overload Resolution

  - by Steve Michelotti

  C# 4 is getting a new feature called named parameters. Although this is a stand-alone feature, it is often used in conjunction with optional parameters. Last week when I was giving a presentation on C# 4, I got a question on a scenario regarding overload resolution that I had not considered before which yielded interesting results. Before I describe the scenario, a little background first. Named parameters is a well documented feature that works like this: suppose you have a method defined like this: 1: void DoWork(int num, string message = "Hello") 2: { 3: Console.WriteLine("Inside DoWork() - num: {0}, message: {1}", num, message); 4: } This enables you to call the method with any of these: 1: DoWork(21); 2: DoWork(num: 21); 3: DoWork(21, "abc"); 4: DoWork(num: 21, message: "abc"); and the corresponding results will be: Inside DoWork() - num: 21, message: Hello Inside DoWork() - num: 21, message: Hello Inside DoWork() - num: 21, message: abc Inside DoWork() - num: 21, message: abc This is all pretty straight forward and well-documented. What is slightly more interesting is how resolution is handled with method overloads. Suppose we had a second overload for DoWork() that looked like this: 1: void DoWork(object num) 2: { 3: Console.WriteLine("Inside second overload: " + num); 4: } The first rule applied for method overload resolution in this case is that it looks for the most strongly-type match first.  Hence, since the second overload has System.Object as the parameter rather than Int32, this second overload will never be called for any of the 4 method calls above.  But suppose the method overload looked like this: 1: void DoWork(int num) 2: { 3: Console.WriteLine("Inside second overload: " + num); 4: } In this case, both overloads have the first parameter as Int32 so they both fulfill the first rule equally.  In this case the overload with the optional parameters will be ignored if the parameters are not specified. Therefore, the same 4 method calls from above would result in: Inside second overload: 21 Inside second overload: 21 Inside DoWork() - num: 21, message: abc Inside DoWork() - num: 21, message: abc Even all this is pretty well documented. However, we can now consider the very interesting scenario I was presented with. The question was what happens if you change the parameter name in one of the overloads.  For example, what happens if you change the parameter *name* for the second overload like this: 1: void DoWork(int num2) 2: { 3: Console.WriteLine("Inside second overload: " + num2); 4: } In this case, the first 2 method calls will yield *different* results: 1: DoWork(21); 2: DoWork(num: 21); results in: Inside second overload: 21 Inside DoWork() - num: 21, message: Hello We know the first method call will go to the second overload because of normal method overload resolution rules which ignore the optional parameters.  But for the second call, even though all the same rules apply, the compiler will allow you to specify a named parameter which, in effect, overrides the typical rules and directs the call to the first overload. Keep in mind this would only work if the method overloads had different parameter names for the same types (which in itself is weird). But it is a situation I had not considered before and it is one in which you should be aware of the rules that the C# 4 compiler applies.

  Read the article

• Default Parameters vs Method Overloading

  - by João Angelo

  With default parameters introduced in C# 4.0 one might be tempted to abandon the old approach of providing method overloads to simulate default parameters. However, you must take in consideration that both techniques are not interchangeable since they show different behaviors in certain scenarios. For me the most relevant difference is that default parameters are a compile time feature while method overloading is a runtime feature. To illustrate these concepts let’s take a look at a complete, although a bit long, example. What you need to retain from the example is that static method Foo uses method overloading while static method Bar uses C# 4.0 default parameters. static void CreateCallerAssembly(string name) { // Caller class - Invokes Example.Foo() and Example.Bar() string callerCode = String.Concat( "using System;", "public class Caller", "{", " public void Print()", " {", " Console.WriteLine(Example.Foo());", " Console.WriteLine(Example.Bar());", " }", "}"); var parameters = new CompilerParameters(new[] { "system.dll", "Common.dll" }, name); new CSharpCodeProvider().CompileAssemblyFromSource(parameters, callerCode); } static void Main() { // Example class - Foo uses overloading while Bar uses C# 4.0 default parameters string exampleCode = String.Concat( "using System;", "public class Example", "{{", " public static string Foo() {{ return Foo(\"{0}\"); }}", " public static string Foo(string key) {{ return \"FOO-\" + key; }}", " public static string Bar(string key = \"{0}\") {{ return \"BAR-\" + key; }}", "}}"); var compiler = new CSharpCodeProvider(); var parameters = new CompilerParameters(new[] { "system.dll" }, "Common.dll"); // Build Common.dll with default value of "V1" compiler.CompileAssemblyFromSource(parameters, String.Format(exampleCode, "V1")); // Caller1 built against Common.dll that uses a default of "V1" CreateCallerAssembly("Caller1.dll"); // Rebuild Common.dll with default value of "V2" compiler.CompileAssemblyFromSource(parameters, String.Format(exampleCode, "V2")); // Caller2 built against Common.dll that uses a default of "V2" CreateCallerAssembly("Caller2.dll"); dynamic caller1 = Assembly.LoadFrom("Caller1.dll").CreateInstance("Caller"); dynamic caller2 = Assembly.LoadFrom("Caller2.dll").CreateInstance("Caller"); Console.WriteLine("Caller1.dll:"); caller1.Print(); Console.WriteLine("Caller2.dll:"); caller2.Print(); } And if you run this code you will get the following output: // Caller1.dll: // FOO-V2 // BAR-V1 // Caller2.dll: // FOO-V2 // BAR-V2 You see that even though Caller1.dll runs against the current Common.dll assembly where method Bar defines a default value of “V2″ the output show us the default value defined at the time Caller1.dll compiled against the first version of Common.dll. This happens because the compiler will copy the current default value to each method call, much in the same way a constant value (const keyword) is copied to a calling assembly and changes to it’s value will only be reflected if you rebuild the calling assembly again. The use of default parameters is also discouraged by Microsoft in public API’s as stated in (CA1026: Default parameters should not be used) code analysis rule.

  Read the article

• Custom Templates: Using user exits

  - by Anthony Shorten

  One of the features of Oracle Utilities Application Framework V4.1 is the ability to use templates and user exits to extend the base configuration files. The configuration files used by the product are based upon a set of templates shipped with the product. When the configureEnv utility asks for configuration settings they are stored in a configuration file ENVIRON.INI which outlines the environment settings. These settings are then used by the initialSetup utility to populate the various configuration files used by the product using templates located in the templates directory of the installation. Now, whilst the majority of the installations at any site are non-production and the templates provided are generally adequate for that need, there are circumstances where extension of templates are needed to take advantage of more advanced facilities (such as advanced security and environment settings). The issue then becomes that if you alter the configuration files manually (directly or indirectly) then you may lose all your custom settings the next time you run initialSetup. To counter this we allow customers to either override templates with their own template or we now provide user exits in the templates to add fragments of configuration unique to that part of the configuration file. The latter means that the base template is still used but additions are included to provide the extensions. The provision of custom templates is supported but as soon as you use a custom template you are then responsible for reflecting any changes we put in the base template over time. Not a big task but annoying if you have to do it for multiple copies of the product. I prefer to use user exits as they seem to represent the least effort solution. The way to find the user exits available is to either read the Server Administration Guide that comes with your product or look at individual templates and look for the lines: #ouaf_user_exit <user exit name> Where <user exit name> is the name of the user exit. User exits are not always present but are in places that we feel are the most likely to be changed. If a user exit does not exist the you can always use a custom template instead. Now lets show an example. By default, the product generates a config.xml file to be used with Oracle WebLogic. This configuration file has the basic setting contained in it to manage the product. If you want to take advantage of the Oracle WebLogic advanced settings, you can use the console to make those changes and it will be reflected in the config.xml automatically. To retain those changes across invocations of initialSetup, you need to alter the template that generates the config.xml or use user exits. The technique is this. Make the change in the console and when you save the change, WebLogic will reflect it in the config.xml for you. Compare the old version and new version of the config.xml and determine what to add and then find the user exit to put it in by examining the base template. For example, by default, the console is not automatically deployed (it is deployed on demand) in the base config.xml. To make the console deploy, you can add the following line to the templates/CM_config.xml.win.exit_3.include file (for windows) or templates/CM_config.xml.exit_3.include file (for linux/unix): <internal-apps-deploy-on-demand-enabled>false</internal-apps-deploy-on-demand-enabled> Now run initialSetup to reflect the change and if you check the splapp/config/config.xml file you will see the change applied for you. Now how did I know which include file? I check the template for config.xml and found there was an user exit at the right place. I prefixed my include filename with "CM_" to denote it as a custom user exit. This will tell the upgrade tools to leave that file alone whenever you decide to upgrade (or even apply fixes). User exits can be powerful and allow customizations to be added for advanced configuration. You will see products using Oracle Utilities Application Framework use this exits themselves (usually prefixed with the product code). You are also taking advantage of them.

  Read the article

• SSAS: Utility to export SQL code from your cube's Data Source View (DSV)

  - by DrJohn

  When you are working on a cube, particularly in a multi-person team, it is sometimes necessary to review what changes that have been done to the SQL queries in the cube's data source view (DSV). This can be a problem as the SQL editor in the DSV is not the best interface to review code. Now of course you can cut and paste the SQL into SSMS, but you have to do each query one-by-one. What is worse your DBA is unlikely to have BIDS installed, so you will have to manually export all the SQL yourself and send him the files. To make it easy to get hold of the SQL in a Data Source View, I developed a C# utility which connects to an OLAP database and uses Analysis Services Management Objects (AMO) to obtain and export all the SQL to a series of files. The added benefit of this approach is that these SQL files can be placed under source code control which means the DBA can easily compare one version with another. The Trick When I came to implement this utility, I quickly found that the AMO API does not give direct access to anything useful about the tables in the data source view. Iterating through the DSVs and tables is easy, but getting to the SQL proved to be much harder. My Google searches returned little of value, so I took a look at the idea of using the XmlDom to open the DSV’s XML and obtaining the SQL from that. This is when the breakthrough happened. Inspecting the DSV’s XML I saw the things I was interested in were called TableType DbTableName FriendlyName QueryDefinition Searching Google for FriendlyName returned this page: Programming AMO Fundamental Objects which hinted at the fact that I could use something called ExtendedProperties to obtain these XML attributes. This simplified my code tremendously to make the implementation almost trivial. So here is my code with appropriate comments. The full solution can be downloaded from here: ExportCubeDsvSQL.zip   using System;using System.Data;using System.IO;using Microsoft.AnalysisServices; ... class code removed for clarity// connect to the OLAP server Server olapServer = new Server();olapServer.Connect(config.olapServerName);if (olapServer != null){ // connected to server ok, so obtain reference to the OLAP databaseDatabase olapDatabase = olapServer.Databases.FindByName(config.olapDatabaseName);if (olapDatabase != null){ Console.WriteLine(string.Format("Succesfully connected to '{0}' on '{1}'",   config.olapDatabaseName,   config.olapServerName));// export SQL from each data source view (usually only one, but can be many!)foreach (DataSourceView dsv in olapDatabase.DataSourceViews){ Console.WriteLine(string.Format("Exporting SQL from DSV '{0}'", dsv.Name));// for each table in the DSV, export the SQL in a fileforeach (DataTable dt in dsv.Schema.Tables){ Console.WriteLine(string.Format("Exporting SQL from table '{0}'", dt.TableName)); // get name of the table in the DSV// use the FriendlyName as the user inputs this and therefore has control of itstring queryName = dt.ExtendedProperties["FriendlyName"].ToString().Replace(" ", "_");string sqlFilePath = Path.Combine(targetDir.FullName, queryName + ".sql"); // delete the sql file if it exists... file deletion code removed for clarity// write out the SQL to a fileif (dt.ExtendedProperties["TableType"].ToString() == "View"){ File.WriteAllText(sqlFilePath, dt.ExtendedProperties["QueryDefinition"].ToString());}if (dt.ExtendedProperties["TableType"].ToString() == "Table"){ File.WriteAllText(sqlFilePath, dt.ExtendedProperties["DbTableName"].ToString()); } } } Console.WriteLine(string.Format("Successfully written out SQL scripts to '{0}'", targetDir.FullName)); } }   Of course, if you are following industry best practice, you should be basing your cube on a series of views. This will mean that this utility will be of limited practical value unless of course you are inheriting a project and want to check if someone did the implementation correctly.

  Read the article

• Scenarios for Throwing Exceptions

  - by Joe Mayo

  I recently came across a situation where someone had an opinion that differed from mine of when an exception should be thrown. This particular case was an issue opened on LINQ to Twitter for an Exception on EndSession.  The premise of the issue was that the poster didn’t feel an exception should be raised, regardless of authentication status.  As first, this sounded like a valid point.  However, I went back to review my code and decided not to make any changes. Here's my rationale: 1. The exception doesn’t occur if the user is authenticated when EndAccountSession is called. 2. The exception does occur if the user is not authenticated when EndAccountSession is called. 3. The exception represents the fact that EndAccountSession is not able to fulfill its intended purpose - to end the session.  If a session never existed, then it would not be possible to perform the requested action.  Therefore, an exception is appropriate. To help illustrate how to handle this situation, I've modified the following code in Program.cs in the LinqToTwitterDemo project to illustrate the situation: static void EndSession(ITwitterAuthorizer auth) { using (var twitterCtx = new TwitterContext(auth, "https://api.twitter.com/1/", "https://search.twitter.com/")) { try { //Log twitterCtx.Log = Console.Out; var status = twitterCtx.EndAccountSession(); Console.WriteLine("Request: {0}, Error: {1}" , status.Request , status.Error); } catch (TwitterQueryException tqe) { var webEx = tqe.InnerException as WebException; if (webEx != null) { var webResp = webEx.Response as HttpWebResponse; if (webResp != null && webResp.StatusCode == HttpStatusCode.Unauthorized) Console.WriteLine("Twitter didn't recognize you as having been logged in. Therefore, your request to end session is illogical.\n"); } var status = tqe.Response; Console.WriteLine("Request: {0}, Error: {1}" , status.Request , status.Error); } } } As expected, LINQ to Twitter wraps the exception in a TwitterQueryException as the InnerException.  The TwitterQueryException serves a very useful purpose through it's Response property.  Notice in the example above that the response has Request and Error proprieties.  These properties correspond to the information that Twitter returns as part of it's response payload.  This is often useful while debugging to help you understand why Twitter was unable to perform the  requested action.  Other times, it's cryptic, but that's another story.  At least you have some way of knowing in your code how to anticipate and handle these situations, along with having extra information to debug with. To sum things up, there are two points to make: when and why an exception should be raised and when to wrap and re-throw an exception in a custom exception type. I felt it was necessary to allow the exception to be raised because the called method was unable to perform the task it was designed for.  I also felt that it is inappropriate for a general library to do anything with exceptions because that could potentially hide a problem from the caller.  A related point is that it should be the exclusive decision of the application that uses the library on what to do with an exception.  Another aspect of this situation is that I wrapped the exception in a custom exception and re-threw.  This is a tough call because I don’t want to hide any stack trace information.  However, the need to make the exception more meaningful by including vital information returned from Twitter swayed me in the direction to design an interface that was as helpful as possible to library consumers.  As shown in the code above, you can dig into the exception and pull out a lot of good information, such as the fact that the underlying HTTP response was a 401 Unauthorized.  In all, trade-offs are seldom perfect for all cases, but combining the fact that the method was unable to perform its intended function, this is a library, and the extra information can be more helpful, it seemed to be the better design. @JoeMayo

  Read the article

• WF4 &ndash; Guess the number game!

  - by MarkPearl

  I posted yesterday how really good WF4 was looking. Today I thought I would show some real basics that I was able to figure out. This will be a simple example, I am going to make a flowchart workflow – which will prompt the user to guess the number until they guess the right number. Lets begin… Make a new project and make it a Workflow console Application. Then select the Workflow file and drag a FlowChart (2) to point 3. This will now show a green start circle in the designer form. We are going to work with primitives to start with. We are now going to drag a few objects onto the Workflow, We drag the WriteLine, Assign & Decision items onto the designer. Once they are dragged onto the designer we will want to link them up. The order that they are linked is critical since this will determine the order of the solution. In this case, we want the system to first ask “Guess a number”, then to wait for the user to input some code, and then to display “You got it” if they got it right, and “Try again” if they got it wrong. So we now link the arrows to the objects. This is done by moving the mouse pointer over the start objects and clicking on one of the toggles and then dragging it to the next object and releasing the button over one of the toggles. This will place an arrow from the source object to the target object. Okay… pretty simple stuff – now we just need these primitive objects to do stuff. Lets start with the WriteLine primitive. We place the text in inverted commas in the Text field. Because this field accepts any valid VB expression we could have put variables etc. in there if we wanted to. The next thing we want to do is allow the user to input a number. This brings up an interesting problem, if a user were to type in a number, there would need to be someway to declare a variable to hold that value for the life of the workflow. We can achieve this by declaring a variable. To declare a variable, move your cursor over the variables tab at the bottom of the workflow, and then type the name of the new variable in the “Create Variable” field and set it as shown in the image above. Now that we have a variable, we want to call the Console.Readline method and assign the inputted value from the Console to that variable. The code that cannot be seen is actually this – Convert.ToInt32(Console.ReadLine()) We now have a workflow that first prompts the user for a number, then allows the user to type in a number. We are almost done, we just need to make the system react to the value inputted. There are a few ways we could do this, I am going to use the Decision item. So select the Decision object on the designer and then view its properties (F4 for me), and in the condition field place a condition. For simplicity sake I have decided that if the user guesses 10, they will have guessed the number. This is now the completed workflow. Its really easy to understand and shows some really powerful principles for Business applications. You can run the application and see what it does. Imagine writing business solutions that do not worry about the exact flow of objects, but simply allows a business analyst or someone to configure the solution to work exactly as the business rules would dictate. And if the rules changed six months later all they would need to do is re-drag some of the flows. Now I do not know if WF4 will allow for this, but it feels like it is a step in the right direct.

  Read the article

• Cannot open root device xvda1 or unknown-block(0,0)

  - by svoop

  I'm putting together a Dom0 and three DomU (all Gentoo) with kernel 3.5.7 and Xen 4.1.1. Each Dom has it's own md (md0 for Dom0, md1 for Dom1 etc). Dom0 works fine so far, however, I'm stuck trying to create DomUs. It appears the xvda1 device on DomU is not created or accessible: Parsing config file dom1 domainbuilder: detail: xc_dom_allocate: cmdline="root=/dev/xvda1 console=hvc0 root=/dev/xvda1 ro 3", features="(null)" domainbuilder: detail: xc_dom_kernel_mem: called domainbuilder: detail: xc_dom_boot_xen_init: ver 4.1, caps xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 hvm-3.0-x86_32p hvm-3.0-x86_64 domainbuilder: detail: xc_dom_parse_image: called domainbuilder: detail: xc_dom_find_loader: trying multiboot-binary loader ... domainbuilder: detail: loader probe failed domainbuilder: detail: xc_dom_find_loader: trying Linux bzImage loader ... domainbuilder: detail: xc_dom_malloc : 10530 kB domainbuilder: detail: xc_dom_do_gunzip: unzip ok, 0x2f7a4f -> 0xa48888 domainbuilder: detail: loader probe OK xc: detail: elf_parse_binary: phdr: paddr=0x1000000 memsz=0x558000 xc: detail: elf_parse_binary: phdr: paddr=0x1558000 memsz=0x690e8 xc: detail: elf_parse_binary: phdr: paddr=0x15c2000 memsz=0x127c0 xc: detail: elf_parse_binary: phdr: paddr=0x15d5000 memsz=0x533000 xc: detail: elf_parse_binary: memory: 0x1000000 -> 0x1b08000 xc: detail: elf_xen_parse_note: GUEST_OS = "linux" xc: detail: elf_xen_parse_note: GUEST_VERSION = "2.6" xc: detail: elf_xen_parse_note: XEN_VERSION = "xen-3.0" xc: detail: elf_xen_parse_note: VIRT_BASE = 0xffffffff80000000 xc: detail: elf_xen_parse_note: ENTRY = 0xffffffff815d5210 xc: detail: elf_xen_parse_note: HYPERCALL_PAGE = 0xffffffff81001000 xc: detail: elf_xen_parse_note: FEATURES = "!writable_page_tables|pae_pgdir_above_4gb" xc: detail: elf_xen_parse_note: PAE_MODE = "yes" xc: detail: elf_xen_parse_note: LOADER = "generic" xc: detail: elf_xen_parse_note: unknown xen elf note (0xd) xc: detail: elf_xen_parse_note: SUSPEND_CANCEL = 0x1 xc: detail: elf_xen_parse_note: HV_START_LOW = 0xffff800000000000 xc: detail: elf_xen_parse_note: PADDR_OFFSET = 0x0 xc: detail: elf_xen_addr_calc_check: addresses: xc: detail: virt_base = 0xffffffff80000000 xc: detail: elf_paddr_offset = 0x0 xc: detail: virt_offset = 0xffffffff80000000 xc: detail: virt_kstart = 0xffffffff81000000 xc: detail: virt_kend = 0xffffffff81b08000 xc: detail: virt_entry = 0xffffffff815d5210 xc: detail: p2m_base = 0xffffffffffffffff domainbuilder: detail: xc_dom_parse_elf_kernel: xen-3.0-x86_64: 0xffffffff81000000 -> 0xffffffff81b08000 domainbuilder: detail: xc_dom_mem_init: mem 5000 MB, pages 0x138800 pages, 4k each domainbuilder: detail: xc_dom_mem_init: 0x138800 pages domainbuilder: detail: xc_dom_boot_mem_init: called domainbuilder: detail: x86_compat: guest xen-3.0-x86_64, address size 64 domainbuilder: detail: xc_dom_malloc : 10000 kB domainbuilder: detail: xc_dom_build_image: called domainbuilder: detail: xc_dom_alloc_segment: kernel : 0xffffffff81000000 -> 0xffffffff81b08000 (pfn 0x1000 + 0xb08 pages) domainbuilder: detail: xc_dom_pfn_to_ptr: domU mapping: pfn 0x1000+0xb08 at 0x7fdec9b85000 xc: detail: elf_load_binary: phdr 0 at 0x0x7fdec9b85000 -> 0x0x7fdeca0dd000 xc: detail: elf_load_binary: phdr 1 at 0x0x7fdeca0dd000 -> 0x0x7fdeca1460e8 xc: detail: elf_load_binary: phdr 2 at 0x0x7fdeca147000 -> 0x0x7fdeca1597c0 xc: detail: elf_load_binary: phdr 3 at 0x0x7fdeca15a000 -> 0x0x7fdeca1cd000 domainbuilder: detail: xc_dom_alloc_segment: phys2mach : 0xffffffff81b08000 -> 0xffffffff824cc000 (pfn 0x1b08 + 0x9c4 pages) domainbuilder: detail: xc_dom_pfn_to_ptr: domU mapping: pfn 0x1b08+0x9c4 at 0x7fdec91c1000 domainbuilder: detail: xc_dom_alloc_page : start info : 0xffffffff824cc000 (pfn 0x24cc) domainbuilder: detail: xc_dom_alloc_page : xenstore : 0xffffffff824cd000 (pfn 0x24cd) domainbuilder: detail: xc_dom_alloc_page : console : 0xffffffff824ce000 (pfn 0x24ce) domainbuilder: detail: nr_page_tables: 0x0000ffffffffffff/48: 0xffff000000000000 -> 0xffffffffffffffff, 1 table(s) domainbuilder: detail: nr_page_tables: 0x0000007fffffffff/39: 0xffffff8000000000 -> 0xffffffffffffffff, 1 table(s) domainbuilder: detail: nr_page_tables: 0x000000003fffffff/30: 0xffffffff80000000 -> 0xffffffffbfffffff, 1 table(s) domainbuilder: detail: nr_page_tables: 0x00000000001fffff/21: 0xffffffff80000000 -> 0xffffffff827fffff, 20 table(s) domainbuilder: detail: xc_dom_alloc_segment: page tables : 0xffffffff824cf000 -> 0xffffffff824e6000 (pfn 0x24cf + 0x17 pages) domainbuilder: detail: xc_dom_pfn_to_ptr: domU mapping: pfn 0x24cf+0x17 at 0x7fdece676000 domainbuilder: detail: xc_dom_alloc_page : boot stack : 0xffffffff824e6000 (pfn 0x24e6) domainbuilder: detail: xc_dom_build_image : virt_alloc_end : 0xffffffff824e7000 domainbuilder: detail: xc_dom_build_image : virt_pgtab_end : 0xffffffff82800000 domainbuilder: detail: xc_dom_boot_image: called domainbuilder: detail: arch_setup_bootearly: doing nothing domainbuilder: detail: xc_dom_compat_check: supported guest type: xen-3.0-x86_64 <= matches domainbuilder: detail: xc_dom_compat_check: supported guest type: xen-3.0-x86_32p domainbuilder: detail: xc_dom_compat_check: supported guest type: hvm-3.0-x86_32 domainbuilder: detail: xc_dom_compat_check: supported guest type: hvm-3.0-x86_32p domainbuilder: detail: xc_dom_compat_check: supported guest type: hvm-3.0-x86_64 domainbuilder: detail: xc_dom_update_guest_p2m: dst 64bit, pages 0x138800 domainbuilder: detail: clear_page: pfn 0x24ce, mfn 0x37ddee domainbuilder: detail: clear_page: pfn 0x24cd, mfn 0x37ddef domainbuilder: detail: xc_dom_pfn_to_ptr: domU mapping: pfn 0x24cc+0x1 at 0x7fdece675000 domainbuilder: detail: start_info_x86_64: called domainbuilder: detail: setup_hypercall_page: vaddr=0xffffffff81001000 pfn=0x1001 domainbuilder: detail: domain builder memory footprint domainbuilder: detail: allocated domainbuilder: detail: malloc : 20658 kB domainbuilder: detail: anon mmap : 0 bytes domainbuilder: detail: mapped domainbuilder: detail: file mmap : 0 bytes domainbuilder: detail: domU mmap : 21392 kB domainbuilder: detail: arch_setup_bootlate: shared_info: pfn 0x0, mfn 0xbaa6f domainbuilder: detail: shared_info_x86_64: called domainbuilder: detail: vcpu_x86_64: called domainbuilder: detail: vcpu_x86_64: cr3: pfn 0x24cf mfn 0x37dded domainbuilder: detail: launch_vm: called, ctxt=0x7fff224e4ea0 domainbuilder: detail: xc_dom_release: called Daemon running with PID 4639 [ 0.000000] Initializing cgroup subsys cpuset [ 0.000000] Initializing cgroup subsys cpu [ 0.000000] Linux version 3.5.7-gentoo (root@majordomo) (gcc version 4.5.4 (Gentoo 4.5.4 p1.0, pie-0.4.7) ) #1 SMP Tue Nov 20 10:49:51 CET 2012 [ 0.000000] Command line: root=/dev/xvda1 console=hvc0 root=/dev/xvda1 ro 3 [ 0.000000] ACPI in unprivileged domain disabled [ 0.000000] e820: BIOS-provided physical RAM map: [ 0.000000] Xen: [mem 0x0000000000000000-0x000000000009ffff] usable [ 0.000000] Xen: [mem 0x00000000000a0000-0x00000000000fffff] reserved [ 0.000000] Xen: [mem 0x0000000000100000-0x0000000138ffffff] usable [ 0.000000] NX (Execute Disable) protection: active [ 0.000000] MPS support code is not built-in. [ 0.000000] Using acpi=off or acpi=noirq or pci=noacpi may have problem [ 0.000000] DMI not present or invalid. [ 0.000000] No AGP bridge found [ 0.000000] e820: last_pfn = 0x139000 max_arch_pfn = 0x400000000 [ 0.000000] e820: last_pfn = 0x100000 max_arch_pfn = 0x400000000 [ 0.000000] init_memory_mapping: [mem 0x00000000-0xffffffff] [ 0.000000] init_memory_mapping: [mem 0x100000000-0x138ffffff] [ 0.000000] NUMA turned off [ 0.000000] Faking a node at [mem 0x0000000000000000-0x0000000138ffffff] [ 0.000000] Initmem setup node 0 [mem 0x00000000-0x138ffffff] [ 0.000000] NODE_DATA [mem 0x1387fc000-0x1387fffff] [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x00010000-0x00ffffff] [ 0.000000] DMA32 [mem 0x01000000-0xffffffff] [ 0.000000] Normal [mem 0x100000000-0x138ffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x00010000-0x0009ffff] [ 0.000000] node 0: [mem 0x00100000-0x138ffffff] [ 0.000000] SMP: Allowing 1 CPUs, 0 hotplug CPUs [ 0.000000] No local APIC present [ 0.000000] APIC: disable apic facility [ 0.000000] APIC: switched to apic NOOP [ 0.000000] e820: cannot find a gap in the 32bit address range [ 0.000000] e820: PCI devices with unassigned 32bit BARs may break! [ 0.000000] e820: [mem 0x139100000-0x1394fffff] available for PCI devices [ 0.000000] Booting paravirtualized kernel on Xen [ 0.000000] Xen version: 4.1.1 (preserve-AD) [ 0.000000] setup_percpu: NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:1 nr_node_ids:1 [ 0.000000] PERCPU: Embedded 26 pages/cpu @ffff880138400000 s75712 r8192 d22592 u2097152 [ 0.000000] Built 1 zonelists in Node order, mobility grouping on. Total pages: 1259871 [ 0.000000] Policy zone: Normal [ 0.000000] Kernel command line: root=/dev/xvda1 console=hvc0 root=/dev/xvda1 ro 3 [ 0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes) [ 0.000000] __ex_table already sorted, skipping sort [ 0.000000] Checking aperture... [ 0.000000] No AGP bridge found [ 0.000000] Memory: 4943980k/5128192k available (3937k kernel code, 448k absent, 183764k reserved, 1951k data, 524k init) [ 0.000000] SLUB: Genslabs=15, HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1 [ 0.000000] Hierarchical RCU implementation. [ 0.000000] NR_IRQS:4352 nr_irqs:256 16 [ 0.000000] Console: colour dummy device 80x25 [ 0.000000] console [tty0] enabled [ 0.000000] console [hvc0] enabled [ 0.000000] installing Xen timer for CPU 0 [ 0.000000] Detected 3411.602 MHz processor. [ 0.000999] Calibrating delay loop (skipped), value calculated using timer frequency.. 6823.20 BogoMIPS (lpj=3411602) [ 0.000999] pid_max: default: 32768 minimum: 301 [ 0.000999] Security Framework initialized [ 0.001355] Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes) [ 0.002974] Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes) [ 0.003441] Mount-cache hash table entries: 256 [ 0.003595] Initializing cgroup subsys cpuacct [ 0.003599] Initializing cgroup subsys freezer [ 0.003637] ENERGY_PERF_BIAS: Set to 'normal', was 'performance' [ 0.003637] ENERGY_PERF_BIAS: View and update with x86_energy_perf_policy(8) [ 0.003643] CPU: Physical Processor ID: 0 [ 0.003645] CPU: Processor Core ID: 0 [ 0.003702] SMP alternatives: switching to UP code [ 0.011791] Freeing SMP alternatives: 12k freed [ 0.011835] Performance Events: unsupported p6 CPU model 42 no PMU driver, software events only. [ 0.011886] Brought up 1 CPUs [ 0.011998] Grant tables using version 2 layout. [ 0.012009] Grant table initialized [ 0.012034] NET: Registered protocol family 16 [ 0.012328] PCI: setting up Xen PCI frontend stub [ 0.015089] bio: create slab <bio-0> at 0 [ 0.015158] ACPI: Interpreter disabled. [ 0.015180] xen/balloon: Initialising balloon driver. [ 0.015180] xen-balloon: Initialising balloon driver. [ 0.015180] vgaarb: loaded [ 0.016126] SCSI subsystem initialized [ 0.016314] PCI: System does not support PCI [ 0.016320] PCI: System does not support PCI [ 0.016435] NetLabel: Initializing [ 0.016438] NetLabel: domain hash size = 128 [ 0.016440] NetLabel: protocols = UNLABELED CIPSOv4 [ 0.016447] NetLabel: unlabeled traffic allowed by default [ 0.016475] Switching to clocksource xen [ 0.017434] pnp: PnP ACPI: disabled [ 0.017501] NET: Registered protocol family 2 [ 0.017864] IP route cache hash table entries: 262144 (order: 9, 2097152 bytes) [ 0.019322] TCP established hash table entries: 524288 (order: 11, 8388608 bytes) [ 0.020376] TCP bind hash table entries: 65536 (order: 8, 1048576 bytes) [ 0.020497] TCP: Hash tables configured (established 524288 bind 65536) [ 0.020500] TCP: reno registered [ 0.020525] UDP hash table entries: 4096 (order: 5, 131072 bytes) [ 0.020564] UDP-Lite hash table entries: 4096 (order: 5, 131072 bytes) [ 0.020624] NET: Registered protocol family 1 [ 0.020658] PCI-DMA: Using software bounce buffering for IO (SWIOTLB) [ 0.020662] software IO TLB [mem 0xfb632000-0xff631fff] (64MB) mapped at [ffff8800fb632000-ffff8800ff631fff] [ 0.020750] platform rtc_cmos: registered platform RTC device (no PNP device found) [ 0.021378] HugeTLB registered 2 MB page size, pre-allocated 0 pages [ 0.023378] msgmni has been set to 9656 [ 0.023544] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 253) [ 0.023549] io scheduler noop registered [ 0.023551] io scheduler deadline registered [ 0.023580] io scheduler cfq registered (default) [ 0.023650] pci_hotplug: PCI Hot Plug PCI Core version: 0.5 [ 0.023845] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled [ 0.024082] Non-volatile memory driver v1.3 [ 0.024085] Linux agpgart interface v0.103 [ 0.024207] Event-channel device installed. [ 0.024265] [drm] Initialized drm 1.1.0 20060810 [ 0.024268] [drm:i915_init] *ERROR* drm/i915 can't work without intel_agp module! [ 0.025145] brd: module loaded [ 0.025565] loop: module loaded [ 0.045646] Initialising Xen virtual ethernet driver. [ 0.198264] i8042: PNP: No PS/2 controller found. Probing ports directly. [ 0.199096] i8042: No controller found [ 0.199139] mousedev: PS/2 mouse device common for all mice [ 0.259303] rtc_cmos rtc_cmos: rtc core: registered rtc_cmos as rtc0 [ 0.259353] rtc_cmos: probe of rtc_cmos failed with error -38 [ 0.259440] md: raid1 personality registered for level 1 [ 0.259542] nf_conntrack version 0.5.0 (16384 buckets, 65536 max) [ 0.259732] ip_tables: (C) 2000-2006 Netfilter Core Team [ 0.259747] TCP: cubic registered [ 0.259886] NET: Registered protocol family 10 [ 0.260031] ip6_tables: (C) 2000-2006 Netfilter Core Team [ 0.260070] sit: IPv6 over IPv4 tunneling driver [ 0.260194] NET: Registered protocol family 17 [ 0.260213] Bridge firewalling registered [ 5.360075] XENBUS: Waiting for devices to initialise: 25s...20s...15s...10s...5s...0s...235s...230s...225s...220s...215s...210s...205s...200s...195s...190s...185s...180s...175s...170s...165s...160s...155s...150s...145s...140s...135s...130s...125s...120s...115s...110s...105s...100s...95s...90s...85s...80s...75s...70s...65s...60s...55s...50s...45s...40s...35s...30s...25s...20s...15s...10s...5s...0s... [ 270.360180] XENBUS: Timeout connecting to device: device/vbd/51713 (local state 3, remote state 1) [ 270.360273] md: Waiting for all devices to be available before autodetect [ 270.360277] md: If you don't use raid, use raid=noautodetect [ 270.360388] md: Autodetecting RAID arrays. [ 270.360392] md: Scanned 0 and added 0 devices. [ 270.360394] md: autorun ... [ 270.360395] md: ... autorun DONE. [ 270.360431] VFS: Cannot open root device "xvda1" or unknown-block(0,0): error -6 [ 270.360435] Please append a correct "root=" boot option; here are the available partitions: [ 270.360440] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) [ 270.360444] Pid: 1, comm: swapper/0 Not tainted 3.5.7-gentoo #1 [ 270.360446] Call Trace: [ 270.360454] [<ffffffff813d2205>] ? panic+0xbe/0x1c5 [ 270.360459] [<ffffffff813d2358>] ? printk+0x4c/0x51 [ 270.360464] [<ffffffff815d5fb7>] ? mount_block_root+0x24f/0x26d [ 270.360469] [<ffffffff815d62b6>] ? prepare_namespace+0x168/0x192 [ 270.360474] [<ffffffff815d5ca7>] ? kernel_init+0x1b0/0x1c2 [ 270.360477] [<ffffffff815d5500>] ? loglevel+0x34/0x34 [ 270.360482] [<ffffffff813d5a64>] ? kernel_thread_helper+0x4/0x10 [ 270.360486] [<ffffffff813d4038>] ? retint_restore_args+0x5/0x6 [ 270.360490] [<ffffffff813d5a60>] ? gs_change+0x13/0x13 The config: name = "dom1" bootloader = "/usr/bin/pygrub" root = "/dev/xvda1 ro" extra = "3" # runlevel memory = 5000 disk = [ 'phy:/dev/md1,xvda1,w' ] # vif = [ 'ip=..., vifname=veth1' ] # none for now Here are some details on the Dom0 kernel (grepping for "xen"): CONFIG_XEN=y CONFIG_XEN_DOM0=y CONFIG_XEN_PRIVILEGED_GUEST=y CONFIG_XEN_PVHVM=y CONFIG_XEN_MAX_DOMAIN_MEMORY=500 CONFIG_XEN_SAVE_RESTORE=y CONFIG_PCI_XEN=y CONFIG_XEN_PCIDEV_FRONTEND=y # CONFIG_XEN_BLKDEV_FRONTEND is not set CONFIG_XEN_BLKDEV_BACKEND=y # CONFIG_XEN_NETDEV_FRONTEND is not set CONFIG_XEN_NETDEV_BACKEND=y CONFIG_INPUT_XEN_KBDDEV_FRONTEND=y CONFIG_HVC_XEN=y CONFIG_HVC_XEN_FRONTEND=y # CONFIG_XEN_WDT is not set # CONFIG_XEN_FBDEV_FRONTEND is not set # Xen driver support CONFIG_XEN_BALLOON=y # CONFIG_XEN_SELFBALLOONING is not set CONFIG_XEN_SCRUB_PAGES=y CONFIG_XEN_DEV_EVTCHN=y CONFIG_XEN_BACKEND=y CONFIG_XENFS=y CONFIG_XEN_COMPAT_XENFS=y CONFIG_XEN_SYS_HYPERVISOR=y CONFIG_XEN_XENBUS_FRONTEND=y CONFIG_XEN_GNTDEV=m CONFIG_XEN_GRANT_DEV_ALLOC=m CONFIG_SWIOTLB_XEN=y CONFIG_XEN_TMEM=y CONFIG_XEN_PCIDEV_BACKEND=m CONFIG_XEN_PRIVCMD=y CONFIG_XEN_ACPI_PROCESSOR=m And the DomU kernel (grepping for "xen"): CONFIG_XEN=y CONFIG_XEN_DOM0=y CONFIG_XEN_PRIVILEGED_GUEST=y CONFIG_XEN_PVHVM=y CONFIG_XEN_MAX_DOMAIN_MEMORY=500 CONFIG_XEN_SAVE_RESTORE=y CONFIG_PCI_XEN=y CONFIG_XEN_PCIDEV_FRONTEND=y CONFIG_XEN_BLKDEV_FRONTEND=y CONFIG_XEN_NETDEV_FRONTEND=y CONFIG_INPUT_XEN_KBDDEV_FRONTEND=y CONFIG_HVC_XEN=y CONFIG_HVC_XEN_FRONTEND=y # CONFIG_XEN_WDT is not set # CONFIG_XEN_FBDEV_FRONTEND is not set # Xen driver support CONFIG_XEN_BALLOON=y # CONFIG_XEN_SELFBALLOONING is not set CONFIG_XEN_SCRUB_PAGES=y CONFIG_XEN_DEV_EVTCHN=y # CONFIG_XEN_BACKEND is not set CONFIG_XENFS=y CONFIG_XEN_COMPAT_XENFS=y CONFIG_XEN_SYS_HYPERVISOR=y CONFIG_XEN_XENBUS_FRONTEND=y CONFIG_XEN_GNTDEV=m CONFIG_XEN_GRANT_DEV_ALLOC=m CONFIG_SWIOTLB_XEN=y CONFIG_XEN_TMEM=y CONFIG_XEN_PRIVCMD=y CONFIG_XEN_ACPI_PROCESSOR=m Any ideas what I'm doing wrong here? Thanks a lot!

  Read the article

• ASP.NET MVC returning ContentResult using Ajax form - how to preserve whitespace?

  - by Ben

  In my application users can enter commands that are executed on the server. The results are added to a session object. I then stuff the session object into ViewData and add it to a textarea. When done with a standard HTML form whitespace is preserved. However, when I swap this out for an ajax form (Ajax.BeginForm) and return the result as ContentResult, the whitespace is removed. Controller Action: [HttpPost] public ActionResult Execute(string submitButton, string command) { if (submitButton == "Clear") { this.CurrentConsole = string.Empty; } if (submitButton == "Execute" && !string.IsNullOrEmpty(command)) { var script = new PSScript() { Name = "Ad hoc script", CommandText = command }; this.CurrentConsole += _scriptService.ExecuteScript(script); } if (Request.IsAjaxRequest()) { return Content(this.CurrentConsole, "text/plain"); } return RedirectToAction("Index"); } View: <fieldset> <legend>Shell</legend> <%=Html.TextArea("console", ViewData["console"].ToString(), new {@class = "console", @readonly = "readonly"})%> <% using (Ajax.BeginForm("Execute", new AjaxOptions { UpdateTargetId = "console", OnBegin = "console_begin", OnComplete = "console_complete"})) { %> <input type="text" id="command" name="command" class="commandtext" /> <input type="submit" value="Execute" class="runbutton" name="submitButton" /> <input type="submit" value="Clear" class="runbutton" name="submitButton" /> <%} %> </fieldset> How can I ensure that whitespace is preserved? When I inspect the response in FireBug it looks like the whitespace is transmitted, so can only assume it has something to do with the way in which the javascript handles the response data.

  Read the article

• jQuery $.ajax Not Working in IE8 but it works on FireFox & Chrome

  - by Sam3k

  I have the following ajax call which works perfectly in Firefox and Chrome but not IE: function getAJAXdates( startDate, numberOfNights, opts ) { var month = startDate.getMonth() + 1; var day = startDate.getDate(); var year = startDate.getFullYear(); var d = new Date(); var randNum = Math.floor(Math.random()*100000000); $.ajax({ type : "GET", dataType : "json", url : "/availability/ajax/bookings?rand="+randNum, cache : false, data : 'month='+month+'&day='+day+'&year='+year+'&nights='+numberOfNights, contentType : 'application/json; charset=utf8', success : function(data) { console.log('@data: '+data); insertCellData(data, opts, startDate); }, error:function(xhr, status, errorThrown) { console.log('@Error: '+errorThrown); console.log('@Status: '+status); console.log('@Status Text: '+xhr.statusText); } }); } I know for a fact that all the variables are passing the right content and $.ajax is indeed passing all the paramater/values. This is what I get on error: LOG: @Error: undefined LOG: @Status: parsererror LOG: @Status Text: OK I'm aware of the cache issue on IE and implemented a random paramater to clear it up. Finally these are the headers that are sent back from the backend: header('Content-Type: application/json; charset=utf8'); header("Cache-Control: no-cache"); header("Expires: 0"); header('Access-Control-Max-Age: 3628800'); header('Access-Control-Allow-Methods: GET, POST, PUT, DELETE');

  Read the article

• jquery ajax using 'addresses' to update url for bookmarking

  - by Jay

  $("document").ready(function(){ contM = $('#main-content'); contS = $('#second-content'); $(contM).hide(); $(contS).hide(); function loadURL(url) { console.log("loadURL: " + url); $.post(url,{post_loader: 1},{post_loader: 1}, function(data){ $(contM).html($(data)); $(contM).show(); }); } // Event handlers $.address.init(function(event) { console.log("init: " + $('[rel=address:' + event.value + ']').attr('href')); }).change(function(event) { $.post($('[rel=address:' + event.value + ']').attr('href'), {post_loader: 1}, function(data){ $(contM).html($(data)); $(contM).show(); }); console.log("change"); }) $('.update-main a').click(function(){ loadURL($(this).attr('href')); }); }); I'm using this code to make calls to a server to update the main content of a web page. Everything works fine in Google Chrome, but fails to execute properly in Firefox. The strange thing is that when I have the console open to monitor server communication, the application works fine, only when it is closed do problems occur : the script starts to communicate with the server, but before it receives the data the browser jumps to the source url. any ideas?

  Read the article

• CallContext and ApplicationHost

  - by p2u

  I tried to create an ApplicationHost. But I had errors like SerializationException and FileNotFoundException. Then I found this blog entry, where it's seem to be a remoting problem. In my little application I use the CallContext, so I tried some approaches. When I empty the CallContext before I create the ApplicationHost, it works: Programm class: namespace ApplicationHostDemo { public class Program { public static void Main(string[] args) { Evil evil = new Evil(); CallContext.SetData(Evil.CALLCONTEXT, evil); CallContext.FreeNamedDataSlot(Evil.CALLCONTEXT); Console.WriteLine("Simple Host-Demo\r\n"); Host host = CreateHost(); CallContext.SetData(Evil.CALLCONTEXT, evil); host.ProcessRequest("Index.aspx"); Console.WriteLine("\r\n\r\nSimple Host-Demo end"); Console.ReadLine(); } public static Host CreateHost() { return (Host)ApplicationHost.CreateApplicationHost(typeof(Host), "/", Directory.GetCurrentDirectory()); } public class Host : MarshalByRefObject { public void ProcessRequest(string page) { SimpleWorkerRequest swr = new SimpleWorkerRequest(page, "", Console.Out); HttpRuntime.ProcessRequest(swr); } } } } Evil class: namespace ApplicationHostDemo { [Serializable] public class Evil : ILogicalThreadAffinative { public const string CALLCONTEXT = "evil"; public string Name { get; set; } } } Do you know or could you explain why it works?

  Read the article

• C# Working with Locking and Threads

  - by aherrick

  Work on this small test application to learn threading/locking. I have the following code, I would think that the line should only write to console once. However it doesn't seem to be working as expected. Any thoughts on why? What I'm trying to do is add this Lot object to a List, then if any other threads try and hit that list, it would block. Am i completely misusing lock here? class Program { static void Main(string[] args) { int threadCount = 10; //spin up x number of test threads Thread[] threads = new Thread[threadCount]; Work w = new Work(); for (int i = 0; i < threadCount; i++) { threads[i] = new Thread(new ThreadStart(w.DoWork)); } for (int i = 0; i < threadCount; i++) { threads[i].Start(); } // don't let the console close Console.ReadLine(); } } public class Work { List<Lot> lots = new List<Lot>(); private static readonly object thisLock = new object(); public void DoWork() { Lot lot = new Lot() { LotID = 1, LotNumber = "100" }; LockLot(lot); } private void LockLot(Lot lot) { // i would think that "Lot has been added" should only print once? lock (thisLock) { if(!lots.Contains(lot)) { lots.Add(lot); Console.WriteLine("Lot has been added"); } } } }

  Read the article

• Sending data through POST request from a node.js server to a node.js server

  - by Masiar

  I'm trying to send data through a POST request from a node.js server to another node.js server. What I do in the "client" node.js is the following: var options = { host: 'my.url', port: 80, path: '/login', method: 'POST' }; var req = http.request(options, function(res){ console.log('status: ' + res.statusCode); console.log('headers: ' + JSON.stringify(res.headers)); res.setEncoding('utf8'); res.on('data', function(chunk){ console.log("body: " + chunk); }); }); req.on('error', function(e) { console.log('problem with request: ' + e.message); }); // write data to request body req.write('data\n'); req.write('data\n'); req.end(); This chunk is taken more or less from the node.js website so it should be correct. The only thing I don't see is how to include username and password in the options variable to actually login. This is how I deal with the data in the server node.js (I use express): app.post('/login', function(req, res){ var user = {}; user.username = req.body.username; user.password = req.body.password; ... }); How can I add those username and password fields to the options variable to have it logged in? Thanks

  Read the article

• Finding perfect numbers in C# (optimization)

  - by paradox

  I coded up a program in C# to find perfect numbers within a certain range as part of a programming challenge . However, I realized it is very slow when calculating perfect numbers upwards of 10000. Are there any methods of optimization that exist for finding perfect numbers? My code is as follows: using System; using System.Collections.Generic; using System.Linq; namespace ConsoleTest { class Program { public static List<int> FindDivisors(int inputNo) { List<int> Divisors = new List<int>(); for (int i = 1; i<inputNo; i++) { if (inputNo%i==0) Divisors.Add(i); } return Divisors; } public static void Main(string[] args) { const int limit = 100000; List<int> PerfectNumbers = new List<int>(); List<int> Divisors=new List<int>(); for (int i=1; i<limit; i++) { Divisors = FindDivisors(i); if (i==Divisors.Sum()) PerfectNumbers.Add(i); } Console.Write("Output ="); for (int i=0; i<PerfectNumbers.Count; i++) { Console.Write(" {0} ",PerfectNumbers[i]); } Console.Write("\n\n\nPress any key to continue . . . "); Console.ReadKey(true); } } }

  Read the article

• Call private methods and private properties from outside a class in PHP

  - by Pablo López Torres

  I want to access private methods and variables from outside the classes in very rare specific cases. I've seen that this is not be possible although introspection is used. The specific case is the next one: I would like to have something like this: class Console { final public static function run() { while (TRUE != FALSE) { echo "\n> "; $command = trim(fgets(STDIN)); switch ($command) { case 'exit': case 'q': case 'quit': echo "OK+\n"; return; default: ob_start(); eval($command); $out = ob_get_contents(); ob_end_clean(); print("Command: $command"); print("Output:\n$out"); break; } } } } This method should be able to be injected in the code like this: Class Demo { private $a; final public function myMethod() { // some code Console::run(); // some other code } final public function myPublicMethod() { return "I can run through eval()"; } private function myPrivateMethod() { return "I cannot run through eval()"; } } (this is just one simplification. the real one goes through a socket, and implement a bunch of more things...) So... If you instantiate the class Demo and you call $demo-myMethod(), you'll get a console: that console can access the first method writing a command like: > $this->myPublicMethod(); But you cannot run successfully the second one: > $this->myPrivateMethod(); Do any of you have any idea, or if there is any library for PHP that allows you to do this? Thanks a lot!

  Read the article

• Perl strings internals

  - by n0rd

  How does perl strings represented internally? What encoding is used? How do I handle different encodings properly? I've been using perl for quite a long time, but it didn't include a lot of string handling in different encodings, and when I encountered a minor problem that had something to do with encodings I usually resorted to some shamanic actions. Until this moment I thought about perl strings as sequences of bytes, which did fit pretty well for my tasks. Now I need to do some processing of UTF-8 encoded file and here starts trouble. First, I read file into string like this: open(my $in, '<', $ARGV[0]) or die "cannot open file $ARGV[0] for reading"; binmode($in, ':utf8'); my $contents; { local $/; $contents = <$in>; } close($in); then simply print it: print $contents; And I get two things: a warning Wide character in print at <scriptname> line <n> and a garbage in console. So I can conclude that perl strings have a concept of "character" that can be "wide" or not, but when printed these "wide" characters are represented in console as multiple bytes, not as single "character". (I wonder now why did all my previous experience with binary files worked quite how I expected it to work without any "character" issues). Why then I see garbage in console? If perl stores strings as character in some known encoding, I don't think there is a big problem to find out console encoding and print text properly. (I use Windows, BTW). If perl stores strings as multibyte sequences (e.g. using same UTF-8 encoding), why is it done this way? From my C experience handling multibyte strings is PAIN.

  Read the article

• .NET Working with Locking and Threads

  - by aherrick

  Work on this small test application to learn threading/locking. I have the following code, I would think that the line should only write to console once. However it doesn't seem to be working as expected. Any thoughts on why? What I'm trying to do is add this Lot object to a List, then if any other threads try and hit that list, it would block. Am i completely misusing lock here? class Program { static void Main(string[] args) { int threadCount = 10; //spin up x number of test threads Thread[] threads = new Thread[threadCount]; Work w = new Work(); for (int i = 0; i < threadCount; i++) { threads[i] = new Thread(new ThreadStart(w.DoWork)); } for (int i = 0; i < threadCount; i++) { threads[i].Start(); } // don't let the console close Console.ReadLine(); } } public class Work { List<Lot> lots = new List<Lot>(); private static readonly object thisLock = new object(); public void DoWork() { Lot lot = new Lot() { LotID = 1, LotNumber = "100" }; LockLot(lot); } private void LockLot(Lot lot) { // i would think that "Lot has been added" should only print once? lock (thisLock) { if(!lots.Contains(lot)) { lots.Add(lot); Console.WriteLine("Lot has been added"); } } } }

  Read the article

• Javascript Detect Control Key Held on Mouseup

  - by Michael Mikowski

  I've searched a good deal, and can't seem to find a satisfactory solution. I hope someone can help. While I am using jQuery, I am also writing many thousands of lines of Javascript. So a "pure" javascript solution is just fine. I'm trying to determine if the control key is physically held down on a mouseup event. That's it; there are no other preconditions. Does anyone know how to do this reliably, cross-browser? I've tried storing this in a state variable by noting when the key is pressed and released: // BEGIN store control key status in hash_state $().bind('keydown','ctrl',function( arg_obj_e ){ hash_state.sw_ctrldn = true; console.debug( hash_state.sw_ctrldn ); }); $().bind('keyup','ctrl',function( arg_obj_e ){ hash_state.sw_ctrldn = false; console.debug( hash_state.sw_ctrldn ); }); // END store control key status in hash_state However, this really doesn't work. If you test this using firebug and watch the console, you will see that auto-repeat seems to happen, and the value toggles. I inspected the mouseup event to see if there is anything useful there, but to no avail: var debugEvent = function( arg_obj_e ){ var str = ''; for ( var attr in arg_obj_e ){ str += attr + ': ' + arg_obj_e[attr] + '\n'; } console.debug(str); } Any help would be appreciated.

  Read the article

• Cannot Cache NHibernate Future Criteria Results

  - by Emilian

  I have the following code: public void FuturesQuery() { using (var session = SessionFactory.OpenSession()) { var blogs = session.CreateCriteria<Blog>() .SetMaxResults(5) .SetCacheable(true) .SetCacheMode(CacheMode.Normal) .SetCacheRegion("BlogQuery") .Future<Blog>(); var countOfBlogs = session.CreateCriteria<Blog>() .SetProjection(Projections.Count(Projections.Id())) .SetCacheable(true) .SetCacheMode(CacheMode.Normal) .SetCacheRegion("BlogQuery") .FutureValue<int>(); Console.WriteLine("Number of blogs: {0}", countOfBlogs.Value); foreach (var blog in blogs) { Console.WriteLine(blog.Title); } } using (var session = SessionFactory.OpenSession()) { var blogs = session.CreateCriteria<Blog>() .SetMaxResults(5) .SetCacheable(true) .SetCacheMode(CacheMode.Normal) .SetCacheRegion("BlogQuery") .Future<Blog>(); var countOfBlogs = session.CreateCriteria<Blog>() .SetProjection(Projections.Count(Projections.Id())) .SetCacheable(true) .SetCacheMode(CacheMode.Normal) .SetCacheRegion("BlogQuery") .FutureValue<int>(); Console.WriteLine("Number of blogs: {0}", countOfBlogs.Value); foreach (var blog in blogs) { Console.WriteLine(blog.Title); } } } I was expecting that the second time I query for blogs and count of blogs I will get values from cache but instead the queries hit the database. If I don't use Futures I get the expected results. Does this means that results from Criteria using futures cannot be cached?

  Read the article

• Big sinatra problems

  - by Joel M.

  Hi, So I'm having huge trouble with sinatra. Here's what I have: require 'dm-core' DataMapper.setup(:default, ENV['DATABASE_URL'] || 'sqlite3://my.db') class Something include DataMapper::Resource property :id, Serial property :thing, Text property :run_in, Integer property :added_at, DateTime property :to, String def schedule cronify(self.thing+" to "+self.to, "http://url"+self.id.to_s, self.run_in) end def notify text(self.thing, self.to) end end Something.auto_upgrade! The cronify method works. I tested it in irb. Also, the schedule instance method works, I tested it in the console. However, it doesn't work in the route, even though it works in the console. post '/add' do @something = Something.create(blah) #this works fine @something.schedule #this works fine in the console; not in the route. end I've tried everything, from @something.create(blah).schedule (which also works fine in the console, but not in the route), to defining the method cronify inside the sinatra helpers, and even calling cronify directly on the route. Nothing works on the route. What am I doing wrong?

  Read the article

• SmtpClient.SendAsync - How to ensure my application doesn't finish before callback?

  - by James

  Hi, I need to send emails asychronously through a console application. I need to do some DB updates on the callback but my application is exiting before the callback code gets run! How can I stop this from happening in a nice manner rather than simply guessing how long to wait before exiting. I would imagine the Async calls get placed in some form of thread? Is it possible to check if any are waiting to be called? Sample Code private static void SendCompletedCallback(object sender, AsyncCompletedEventArgs e) { // Get the unique identifier for this asynchronous operation. String token = (string) e.UserState; if (e.Cancelled) { Console.WriteLine("[{0}] Send canceled.", token); } if (e.Error != null) { Console.WriteLine("[{0}] {1}", token, e.Error.ToString()); } else { // update DB Console.WriteLine("Message sent."); } } public static void Main(string[] args) { var users = Repository.GetUsers(); SmtpClient client = new SmtpClient("Host"); client.SendCompleted += new SendCompletedEventHandler(SendCompletedCallback); MailAddress from = new MailAddress("[email protected]", "System", Encoding.UTF8); foreach (var user in users) { MailAddress to = new MailAddress(user.Email); MailMessage message = new MailMessage(from, to); message.Body = "This is a test"; message.BodyEncoding = System.Text.Encoding.UTF8; message.Subject = "test message 1" + someArrows; message.SubjectEncoding = System.Text.Encoding.UTF8; string userState = String.Format("Message for user id {0}", user.ID); client.SendAsync(message, userState); message.Dispose(); } // need to wait here until I have received a callback for each message // otherwise the application will exit }

  Read the article

< Previous Page | 70 71 72 73 74 75 76 77 78 79 80 81  | Next Page >